S2, E3: Paul Martin is in Gloucestershire today, at Berkeley Castle, owned and lived in by the same family for almost 900 years. This Norman fortress holds an extraordinary archive collection and in 2004, seven lost arias by Vivaldi were discovered amongst the old documents. On today’s show one of the arias will be performed on television for the very first time. Elsewhere Clare Balding gets access to the photographic archive of Country Life magazine in order to investigate how the 115 year old collection has helped to restore the most unlikely of country house interiors. Architect Charlie Luxton is only too happy to go behind the scenes and sing the praises of a famous and much-loved piece of 1960s concrete architecture – London’s BT Tower. Guesting in this episode, double Olympic Champion (and former army sergeant) Dame Kelly Holmes reveals the history of a forgotten piece of military hardware that changed the course of World War II – the Matilda Tank.